Heater for shoe fillers



Sept. 26, 1933.

M. O. JENNINGS HEATER FOR SHOE FILLERS Original Filed Nov. 8, 1930 2Sheets-Sheet l SePt- 26, 1933. M. o. JENNINGS HEATER FOR SHOE FILLERS 2Sheets-Sheet 2 lllllllllllllllllllllllllllllll l `.5. u.:

Ori tinal Filed Nov. 8, 1930 fidi/fa Patented Sept. 26, 1933 UNITEDSTATES HEATER FOR SHOE FILLERS Melvin 0. Jennings, East Lexington,Mass., as-

signor to Harry Mass.

Application 9 Claims.

This invention relates to a heater' for conditioning shoe fillingmaterial which is composed of ground cork or the like mixed with athermoplastic binder. Shoe filler materials of this type are in wide useand are employed to fill the shallow cavity on the under face of theinner sole of a shoe, this cavity being defined by a surrounding ridgecn the welt of the shoe. Filler of this type is customarily applied tothe bottoms of partly made shoes by an operator using a tool somewhatsimilar to a putty knife. In order to facilitate, the operation ofapplying shoe filler, the filler is customarily heated to a sufficienttemperature to render it loose and of a somewhat mealy consistency sothat a portion can be scooped up on the knife blade and molded into therecess in the shoe bottom by a sweep of the blade. It is an object ofthis invention to provide a heater adapted to condition the blocks orloaves of cold filler which may be placed therein, and to present theconditioned ller in a convenient and accessible position for theoperator. It is a further object of the invention to provide apparatuswhich is simple and eflicacious and which cannot injure the filler byoverheating.' Other advantageous features of the invention will beapparentto one skilled'in the art from the disclosure thereof in thefollowing description and on the drawings, of jwhichr- Figure l is afront'elevation of apparatus embodying the invention.

Figure 2 is a side elevation of the same.

Figure 3 is a fragmentary section of the same inY a sectional plane;

Figure 4 is'4 a section of the apparatus on the line 4 4 of Figure l.

Figure 5 is a fragmentary section on the line 5-5 of Figure 4.

Figure 6 isa section on the line 6-6 of Figures 2 and 4. l

' `rFigure 7 is a section on the line 7--7 of Figure 4.

Figure 8 is a fragmentary section on the line 8-8 of `Figure 1.

Figure 9 is a fragmentary section showing a modified form of wallstructure.

Figure 10 is a wiring diagram of the heating circuits of the apparatus.

Referring to the drawings in detail. the apparatus comprises a reservoir2O adapted to hold a considerable quantity of shoe filler. Thisreservoir is provided with a suitable lid or cover 21 at the top thereofand opens'into a basin 22 below and infront thereof. I have discoveredconditioned `shoe filler is far less liable to stick Ito a smooth Monelmetal surface than it is to other metal surfaces. Hence the reservoirand basin are preferably made in such a way as to present smooth Monellmetal surfaces to the filler contained therein. This facilitates agravity H. Beckwith, Brookline,

November 8, 1930, Serial No. 494,316 Renewed August 17, 1933 feed ofliller from the reservoir into the basin. The bottom or floor 23 of thereservoir is preferably of Monel metal and is sloped so that llermaterial, after being conditioned, tends to liow from the reservoir 20into the basin 22. The basin may be provided with a cover 24 to conservethe heat within the basin and container -when the former is not in use.This cover may be folded back on suitable hinges 25 to present the llerin the basin to the operator. As indicated in Figure 4, side walls ofthe reservoir 20 include three spaced shells of sheet metal, some or allof which may be corrugated for strength as shown in Figure 8. The spacebetween the outer shell 26 and the middle shell 27 is preferably filledwith a suitable heat insulating material 3G. This may be ground cork,fiber, or any other material suitable for the purpose. Between themiddle shell 2'? and the inner shell 3l is a space 32 partly filled witha liquid, such as oil or water, for transferring distributing heat fromthe heaters to the inner surfaces of the reservoir and basin. Thus aninsulated jacket for the liquid is provided on all four sides and alsoon the bottom of the reservoir 20. The inner shell 31 is preferably ofMonel metal and is spaced only about half an inch from the middle shell27. This is sufficient to permit free circulation of liquid therein, butreduces to a minimum 'the quantity of liquid to be heated for warmingthe interior of the basin and reservoir. Two sides and bottom of thebasin may thus be heated, but the front wall of the basin is preferablyunheated, this wall having enly the heat insulating layer between shellsfor 'the comfort and protection of the operator who stands close to thefront of the basin. To augment the heating effect of the side walls Imay increase the heated area presented to the contents of the reservoirby installing within the reservoir a heated member 33 which preferablyprojects 'upwardly from the bottom of the reservoir, and which may alsoproject laterally from a side thereof. As shown in Figure 6, thisadditional heating member may be in the form of a wedge extendingforwardly from the rear wail of the reservoir to approximately thecenter of the reservoir. This structure carries the heat into the centerof the mas-s of filler and thus aids materally in maintaining the entiremass of filler at the desired temperature. The member 33 is made with adouble wall forming a jacket coinmunicating with the jacket around thesides and bottom of the reservoir. The inner shell or lining of themember 33, which presented to the filler, is preferably made of Monelmetal to avoid sticking of the filler thereto. The jacket on the bottomof the reservoir is heated directly by any suitable means, such as steampipes or electrical units which. may be secured against the outer shellof the bottom jacket. The liquid heated in the bottom jacket circulatesfreely by gravity up through the side walls and the central column.

In order to regulate the heating of the liquid, I may provide a suitablethermostat 42 having a bulb 43 inserted in the jacket 36 at anyconvenient point. The thermostat may be set to operate at any desiredtemperatures. For example, it may be set to close a heating circuit whenthe teniperature of the liquid falls to 204 F., and to open the circuitwhen the liquid rises to 2080 F. This is sufficient to keep ordinarycommercial termoplastic shoe ller in proper condition for use with nodanger of burning" or harming the ller. As indicated in Figure i0, thethermostat 42 may be employed 'to turn on and off a relatively powerfulheating unit 44 to augment the heating effect of a smaller unit 45 whichis turned on and off only by the main switch 46. 'Ihe latter is a singleon-and-oif switch by which the current for the entire apparatus isturned on and o.

If a liquid such as a suitable oil be 'used in thf` jacket surroundingthe reservoir, the vaporization of the liquid et the operating'temperatures ci. the heater will be negligible so that the supply ofoil in the jacket will ordinarily need to be replenished only at longintervals. The use of a suitable oil is also advantageous because withits use the thermostat can be set to maintain a temperature higher thanthe atmospheric boiling point of water. Higher temperatures can thus bemaintained for special kinds of shoe filler which may require them.Moreover, I have found that the heat transfer from the heating units toa suitable oil, such, for example, as a light mineral oil, is especiallyefficient, as is also the transfer of heat from such oil to the liningof the reservoir. 'Iiius when the heater is turned on at the beginningof the days work, the efficient distribution of the heat to the interiorof the reservoir and basin quickly conditions the filler therein. Incase it is desired to use water or other' liquid liable to evaporate, Imay provide an auxiliary tank 5i) which may be attached to a side of thereservoir 20 and may communicate with the jacket as by a passage 5l nearthe bottom of the tank. A vent 52 may lead from the jacket into theupper' part of the tank to permit the escape of vapor which may risefrom the warmed liquid in the jacket. Since the liquid need be heatedonly to a temperature well below the atmospheric boiling point of water,the loss of water during operation is slight.

In order to assist the operator in smoothing and packing the fillerwhich has been inserted in a shoe, a heating roll S0 may be mounted on across bar 6l which is carried by a pair of uprights 62, 63. The rollpreferably provided with an internal heating unit such as an electricalresistance unit by which it is maintained at a suitable temperature assoon the current is turned on in the circuits of the apparatus. Mountedadjacent to the roll 60, or in any other suitable or convenientposition, is a knife block adapted to receive the blades of knives andto heat these blades to prevent sticking of the filler thereto and tofacilitate the spreading of a iiller in the shoe.

I claim:

1. Apparatus for conditioning shoe filler, which comprises a reservoirhaving a forwardly sloping bottom, a basin projecting forwardly from thelower part of said. reservoir, a thin jacket for liquid on the sides andbottom of said reservoir, means for maintaining said jacketsubstantially filled with liquid, and means for maintaining the liquidin the jacket at a substantially constant temperature.

2. Apparatus for conditioning shoe filler, which comprises a reservoirhaving a forwardly sloping floor, a basin projecting forwardly from thelower portion of said reservoir, a wedge-shaped heat distiibuting memberprojecting laterally from a wall of the reservoir, a jacket for liquidsurrounding and underlying the reservoir and means for maintaining saidliquid at a substantially constant predetermined temperature.

3. Apparatus for conditioning shoe ller, comprising a reservoir forfiller material, a basin projecting from the lower portion of saidreservoir, a jacket for heat-distributing liquid surrounding andunderlying said reservoir and means for maintaining said liquid at asubstantially constant temperature, said means including an electricheating unit against the bottom jacket, a second heating unit contiguousto a portion of said jacket, and a thermostat for automaticallycontrolling the current supply to said second heating unit in accordancewith the temperatures of the liquid in said jacket.

4. Apparatus for conditioning shoe filler, which comprises a reservoirfor ller, a basin projecting forwardly from the lower part of saidreservoir, a thin jacket on the sides and bottom of said reservoir, anoily liquid in said jacket, and means for maintaining said liquid at asubstantially constant temperature.

5. Apparatus for conditioning shoe nller, which comprises a reservoirfor filler, a basin projecting forwardly from the lower part of saidreservoir, said reservoir having triple side walls consisting of aninner, a middle and an outer shell, heat insulating material between theouter and middle shells, and liquid between said middle and innershells, and means for maintaining said liquid at a substantiallyconstant temperature.

6. Apparatus for conditioning shoe filler, which comprises a reservoirhaving a forwardly sloping floor with a Monel metal surface, a basinprojecting forwardly from the lower portion of said reservoir, saidbasin having a substantially horizontal oor which is a continuation ofthe sloping fioor of said reservoir, and means for heating said floors.

7. Apparatus for conditioning shoe ller, which comprises a reservoir forshoe filler having an inner and an outer wall, said inner wall having areentrant portion projecting inwardly, and a jacket forheat-distributing liquid adjacent to said inner wall including thereentrant portion thereof.

8. Apparatus for conditioning shoe ller, comprising a reservoir forshoe-filling material having a forwardly sloping floor, a basinprojecting forwardly from the lower portion of said reservoir, awedge-shaped heat-distributing member projecting forwardly from the rearwall of said reservoir, and a jacket for heat-distributing liquid behindthe surfaces of said member which are exposed to the interior of saidreservoir.

9. Apparatus for conditioning shoe filler, comprising a reservoir forfiller material, a basin j projecting from the lower portion of saidreservoir, a jacket for heat-distributing liquid surrounding andunderlying said reservoir, and means for heating said liquid, saidheating means including a plurality of electrical heating units and athermostat responsive to the temperature of said liquid for turning onand off one of said heating units.

MELVIN O. JENNINGS.

